LIBRARY OF CONGRESS. 

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UNITED STATES OF AMERICA. 



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THEORY AND PRACTICE 

. . . OP • • • 

Lead Burning 

• • • BY THE • • . 

Autogenous Process 

• . • WITH • . • 

/ 

FULL INSTRUCTIONS TO THE AMATEUR v 
IN THE DETAILS OP THE MACHINE AND 
THE MANAGEMENT OP THE GASES. WITH ^ 

VALUABLE SUGGESTIONS AND DIREC- 
TIONS FOR PRACTICE. 



AN EXPERT. 
Pittsburgh. Pa.. 1892. 







COPYRIGHTED. 1892. 



cA^ 



^ 






ADDRESS ALL ORDERS, COMMUNICATIONS OR INQUIRIES TO- 

Bailby-Farrell Mfg. Co., 

619 AND 621 Smithfield St.. PITTSBURGH. PA. 



1892 
JAMES McMILLIN. Printer. 

Ill THIRD AVE.. PITTSBURGH. 



bead Burping. 



TTx EAD burning or the joining or uniting 
Jj^g, of separate pieces of sheet lead, or lead 
pipe, by the autogenous process, is be- 
yond doubt of considerable antiquity. 

In the year 1801, Robert Hare, M. D., 
Professor of Chemistry in the Universit}^ of 
Pennsylvania, observed that a jet of hydrogen, 
when inflamed with atmospheric air — of which 
only one-fifth is oxygen — was productive of a 
heat of pre-eminent intensity ; was led to infer 
that in combining with pure oxygen — the gas 
in question — a temperature at least five times 
as great ought to be produced. 

Experiments made during late years by 
skillful scientists have shown that the heat 
produced by the combustion of pure hydrogen 
and oxygen gases, altliough much more intense, 
was not anything near five times as great as 
that produced by using the atmospheric air 
instead of pure oxygen. 



6 

The result of this observation led Dr. Hare 
to make extensive experiments — extending 
through a series of years — in the construction 
of an apparatus to manage and control a mix- 
ture of hydrogen and oxygen ^ases, with a view 
to use the same for the reduction of platinum. 

A full description of the apparatus and 
experiments was published in the Journal of 
the Franklin Institute in the year 1847. 

The difference between the oxy-hydrogen 
blow-pipe of Dr. Hare, and the sero-hydrogen 
blow-pipe, that we bring it to the attention of 
our readers is: In the former pure oxygen and 
hydrogen gases are mixed in the exact propor- 
tions of two volumes of hydrogen gas, to one 
volume of oxygen gas ; these proportions of gases, 
when combined under pressure, constitute water, 
and when the combined gases are burnt through 
a jet, under pressure, they evolve the most in- 
tense heat yet produced. 

(It is remarkable that oxygen gas, the 
presence of which is necessary before the phe- 
nomenon of burning can take place, and hydro- 
gen gas, that burns Avith a pale blue flame. 



the combinatioQ of tliese two gases forms water, 
which is the opposing element of fire.) 

In the latter or aero-hydrogen blow-pipe 
apparatus, shghtly impure hydrogen gas in com- 
bination with the atmosphere, under pressure, 
in the proportions of two volumes of hydrogen 
gas to one volunie of atmospheric air, is found 
to be most economical and efficient for all the 
purposes of lead burning. 

The aero-hydrogen apparatus is supposed 
to have been introduced in France, and adapted 
to the burning of lead by Count de Eichmont, 
about the year 1830. A machine of the same 
construction w^as patented in England by Luke 
Herbert, in the year 1838. 

It is evident that the art of lead burn- 
ing is exceedingly old, and yet the machine 
and process is practical and efficient for the pur- 
pose intended. 

It is singular that the knowledge and use 
of the autogenous soldering process, although 
introduced over fifty years ago, is still confined 
to a few expert lead workers, whose principle 
business consists in the erection of leaden 



vessels and chambers for use in manufacturing 
sulphuric acid, and in the lining of agitators 
and tanks with lead, in the various processes 
of refining petroleum oil and for other chemical 
purposes. 

We think the reason for this state of 
affairs is, that practical working macliines, built 
by experienced makers, have not been offered to 
the trade. 

It is necessary to have a burning machine 
and to know how to use it in order to make 
a new machine, and if turned out by any but 
an expert are likely to prove complicated, in- 
effective and dangerous. 

Another reason is, that the few experts 
pursuing this branch of the plumbing trade con- 
sider the process of lead burning as a trade 
secret and are not overly anxious to impart 
knowledge to their fellow craftsmen. 

The possession of a lead burning machine 
does not, by any means, make a lead burner of 
the amateur. 

The plumber never forgets the amount of 
practice and time he expended in learning how 



to wipe a solder joint; there is a cunning or 
sleight-of-hand about it that cannot be taught 
a pupil by word of mouth, but can only be 
acquired by observation and practice. So it is 
with lead burning, after much practice, the blow 
pipe becomes your servant, and it is as easily 
managed as the plumber's wiping cloth in mak- 
ing a solder joint. 

The secret once learned stays with you 
always. 

AVe can hardly blame the expert at lead 
burning for withholding the secret he prizes so 
highly, and by reason of his knowledge there- 
of, holds a profitable position. 

It is well that the workman understand 
the nature and properties of the elements by 
means of which he seeks to obtain certain re- 
sults. We will therefore examine in detail 
the peculiar properties of Hydrogen and Oxygen, 
and the means by which these simple elements 
are controlled and made available for the pur- 
pose of autogenous soldering or uniting of 
separate pieces of lead (Per. Se.) without the use 
of the usual tin solder. 



10 



Hydrogen. 



YDKOGEN is the lightest known form 
of matter. Its equivalent combining, 
or atomic Aveight, is below that of all 

other known substances and is represented in 

chemistry by the symbol Hi. 

Hydrogen is an incondensible aeriform 
fluid. It is not absorbable by water, has no 
taste, and when pure is inodorous, but it usu- 
ally has a slight disagreeable smell. Hydrogen 
is recognized as a simple element and the most 
combustible body in nature, and contains the 
greatest number of heat units. 

Hydrogen gas for our purpose is obtained 
by the action of commercial zinc upon diluted 
sulphuric acid. Pure zinc is very slowly acted 
on by dilute sulphuric acid. We sometimes 
find commercial zinc so pure as to yield hydro- 
gen very tardily. The impurities of hydrogen. 



11 

derived from the zinc of commerce, consists of 
carbon and traces^ of sulphur and arsenic. 
These impurities do not interfere to any great 
extent in the use of the hydrogen gas for our 
purpose. 



12 



Oxygen. 

Z^^XYGEN is more abundantly diffused 
V^iyX^ throughout nature than any other 
elementary body. Jt forms eight-ninths 
of the weight of water and one-fifth of the 
weight of the atmosphere and a large relative 
proportion of the mineral bodies which form 
the solid matter of the globe. 

It is also an element of all organized 
bodies, both animal and vegetable. 

Oxygen gas is insipid, colorless and ino- 
dorous and permanently elastic under all known 
pressures and temperatures. It is a powerful 
supporter of combustion. 



13 



Hydrogen apd Oxygen, 

Considered together, exhibit many remarkable 
properties. 

Hydrogen, during combustion, combines 
witli eight times its weight of oxygen. 

Hydrogen explodes most violently when 
the mixture of one volume of hydrogen with 
three volumes of atmospheric air is ignited. 

If, instead of a mixture of atmospheric air, 
two Yohimes of hydrogen and one of i^ure 
oxygen be ignited, the explosion is extremely 
violent. 

When two volumes of pure hydrogen gas 
are mixed with one vohime of oxygen gas, and 
the mixture inflamed in a proper apparatus 
by the electric spark, the gases totally disappear 
at the moment of explosion or combination and 
water equal to the weight of the gases con- 
sumed is formed. Combustion, therefore, can- 
not be regarded as dependent \x\>ox\ any peculiar 



u 

principle or form of matter, but must be re- 
garded as a general result of intense chemical 
action. 

This disposition to explode must not l)e 
forgotten in working with the lead burning 
machine. 

The introduction of atmospheric air into 
the hydrogen flame, issuing from a blow-pipe 
jet, exhibits two distinct figures : the internal 
flame, which is conical, blue, and well defined^ 
at the apex of which the most intense degree 
of heat is evolved, this is known as the deoxi- 
dizing or reducing flame; the external flame is 
red, vague and undetermined and of inferior 
temperature to the former, and known as the 
oxidizing flame. 

It may be observed that the hydrogen gas 
is the combustible and the oxygen contained in 
the atmospheric air the supporter of combustion. 

The quantity of atmospheric air that con- 
tains the exact proportion of oxygen, which, if 
chemicallv combined with the hvdrogen, would 



15 

produce water, evolves the most intense heat 
from any given quantity of hydrogen gas issu- 
ing from the blow-pipe jet. 



The lead burner's flame, when skillfully 
adjusted to the exact volumes of hydrogen gas 
and air, will show moisture on the lead seam 
slightly in advance of the jet. This is caused 
by the chemical combination of portions of the 
burning gases. 

The terms oxidizement and oxidation im- 
ply the combination of oxygen with bodies, and 
its abstraction or separation is deoxidizement or 
reduction. 



All elementary substances are susceptible 
of oxidizement, and most of them at certain 
temperatures, with the evolution of heat and 
light ; these are, in common language, termed 
combustible or inflammable bodies; when a sub- 
stance is saturated with oxygen it becomes in- 
combustible; that is, incapable of entering into 
further combination with oxvgen. An excess of 



16 

atmospheric air or oxygen forced under pressure 
into ignited hydrogen gas, issuing from a jet, 
will extinguish the flame. 

The point to be recognized and utilized 
by the lead burner is to keep the deoxidizing 
flame only on the work to be done. 



Apparatus. 



n^^;gl[' UMER0T7S methods and machines of 
jlf^N various designs have been nsed dur- 
ing the past fifty years to control and 
adapt the mixed hydrogen and oxygen gases to 
the purposes of the lead burner, many of which 
were unnecessarily complicated and some highly 
dangerous. 

The want of a simple, safe, practical ma- 
chine and full instructions how to use the same, 
has i)revented the plumbing trade generally 
from taking advantage of and profiting by this 
quick, cheap way of soldering or joining lead 
without solder. 

AVe now give the reader a full and clear 
description of a simple, safe and practical appa- 
ratus for controling and adapting the mixed 
gases for soldering lead joints. 

B 



18 

It seems to us that it would be profitable 
for every plumber to have a Lead Burniug Ma- 
chine in his shop, properly charged, ready for 
use. 

It would certainly save its cost in tin 
solder durino: the vear. 



19 




Hydrogen Gas Generator. 



Hydrogen Gas Generator. 



^^jI^HIS consists of the gas generating cham- 
Vl|7 ber, C, Fig. 2. The copper perforated 
tray, G. The inlet and exit acidulated 
water supply pipe, F. The acidulated water res- 
ervoir, B. The brass trap screw or inlet, A^ to 
the gas generating chamber, C. Safety chamber, 
E. The fire-trap pipe, 0. Hydrogen cock. K. 
And cleaning out or drain plug, D. Charging 
inlet, P. 

On receipt of a Hydrogen Gas Generator 
from the maker, do not fail to properly test the 
same, to prove that it is perfectly air tight be- 
fore introducing the gas generating charge of 
sulphuric acid. 

This can be done in the following man- 
ner : Close the hydrogen cock " K," examine 
the cap of the drain vent '' D," and see that the 
Avasher contained therein has a tight bearing on 



21 

the male end of tlie drain plug, f^crew same up 
tiulit. Through the inlet or trap-screw "A," in- 
troduce and distribute regularly over the per- 
forated tray '' G," 20 to 25 pounds of commer- 
cial spelter, l)roken in lumps of from one inch 
to two inches in diameter, the idea being to 
have all the zinc surface possible to act on the 
acidulated water, but not to have any small par- 
ticles of zinc that would fall through the holes 
in the ])erforated tray '"G." 

Examine carefully the leaden washer on 
the trap-screw "A," as it must make a gas-tight 
joint. A small quantity of tallow will assist in 
making a tight bearing. Screw the plug up 
tight 

You now have presumably a tight gas 
generating compartment containing the charge 
of zinc, from the action of which, on the acidu- 
lated water, we propose to generate hydrogen 
^^as. 

It will not, however, do to presume or 
take for granted the tightness of the gas cham- 
ber. In working Avith hydrogen gas, it must be 
known to a certainty that the gas cannot escaj^e, 



22 

except through the outlet or regulating cock 
" K." We therefore recommend the amateur 
not to take any chances of a leak of hydrogen 
gas, but to make a certain test for the tightness 
of the gas generating chamber, by means of 
plain water and atmospheric air. 

Proceed as follows : Open the hydrogen 
cock "K,'' pour into the opening ^'P" of the 
acidulated water reservoir " B " plain water, 
until the water shows itself or spurts out of the 
hydrogen gas cock '' K." 

This operation proves that the generating 
chamber " C " and safety chamber " E " is com- 
pletely filled with plain water. 

Now connect the air-pump "R" to the 
hydrogen cock ''K," by means of the six-foot 
piece of rubber tubing that belongs to and 
comes with the air-pump. 

About forty strokes of the air-pump will 
fill the gas chamber "C" with atmospheric air, 
and drive the water out of the gas generating 
chamber ''C" through the pipe ' F" into the 
reservoir chamber "B," this water will stand 
about on the line "S;" a continued working of 



23 

tlie air-pump will only blow the' excess of air 
up through the water in the supply pipe "F" 
and reservoir "B," and escape through the open- 
ing or inlet ''P," in puffs or blows, keeping the 
water boiling or in a state of ebullition until 
the pumping of air into the generator ceases ; 
the water will then quietly settle at the line 
"8" in the reservoir chamber ''B" if all be 
tight. 

Now, shut the hydrogen cock "K" and 
let the gas generator stand for at least one 
hour. If there is the slightest leak of atmos- 
pheric air, it Avill be known by the water in the 
reservoir " B" receding, and if sufficient time is 
given the Avater will aL>;ain fill the generating 
chamber "C." 

There is nothing to be done but to find 
the leak, and, in most cases, this will be found 
in the washer of the trap-screw "A." 

The ex])ert lead burner has no trouble in 
making his machine tight. 

The amateur will learn by experience the 
penetrating qualities of hydrogen gas and soon 
be able to keep a tight gas generating chamber 



and so guard against explosions by the acci- 
dental igniting of the escaping hydrogen gas. 

Having proved the hydrogen gas genera- 
tor to be perfectly air tight by the plain water 
standing steadily at the line "S/' in the acidu- 
lated water reservoir "B," we proceed to find, 
by means of plain water, the exact fluid capacity 
of the generator, or, in other words, the exact 
quantity of fluid that can be used as a working 
charge when the acidulated water is used. 

As the generator now stands, we have 
pumped the chamber "C" full of atmospheric 
air, forcing out the plain water into the reser- 
voir "B," any excess of air by continued [mmp- 
ing escapes through the opening "P." The 
"quantity of water now in the generator is its 
full working charge of fluid that the generator 
is capable of containing. 

This point must be carefully noted, as it 
would be extremely troublesome to the operator, 
should he overcharge the generator with acidu- 
lated fluid. 

If this quantity of fluid is increased in 
actual practice, the machine will overflow or 



blow at " P." If a less quantity of fluid is used 
the full capacity of the gas s^enerator will not be 
available. It is, therefore, of importance to the 
lead burner to know the exact quantity of the 
water and acid required to obtain the best re- 
sults from the generator. 

For the purpose of recording for u-e, the 
exact quantity of the fluid charge, take the ma- 
chine as it now stands, with the plain water 
standing in the reservoir chamber " B," at the 
hne "S," open the hydrogen cock "K" and 
allow all the air to escape. Then unscrew the 
cap from the drain outlet "D," and coUect the 
escaping water. 

The quantity of water now collected is 
the full fluid cai:>acity, or the quantity of the 
full working charge of the gas machine, and 
when charging the machine for active Avork in 
generating hydrogen gas with Avater and sul- 
phuric acid, the combined quantity of the Avater 
and acid must not exceed the total quantity of 
Avater noAV collected from the machine. 

From the water thus taken from the gen- 
erator, discard or throAV away one-sixth part, 



26 

the remaining five sixths pour into the reservoir 
'^B/' after having shut the h^^lrogen cock "K," 
and tightened up the vent or drain plug ^'D/' 

Now take of commercial sulphuric acid, 
a quantity equal to the water thrown away, or 
the one-sixth part of the full fluid capacity of 
the gas generator and carefully pour the acid 
into the opening ''P" of the reservoir cham- 
ber ^'B." 

The immediate results will be the evolu 
tion of heat by the condensation of the sul- 
phuric acid and water, the acid sours and pene- 
trates every portion of the Avater. This combi- 
nation of sulphuric acid and water is acted on 
by the zinc, which liberates hydrogen gas from 
the Avater ; this gas, by reason of its lightness, 
rises to the top of the chamber "C,'' and, as it 
accumulates pressure, drives the acidulated Avater 
aAvay from the zinc and into the reserA'oir ''B,'' 
thus causing the further production of hydrogen 
gas to cease. 

The hydrogen gas generator is noAV fully 
charged and ready to supply hydrogen gas at 
the call of the AAorkman, as desired. 



27 

The directions given will enable the ame- 
teur to determine the exact quantity of the 
working acidulated fluid charge for a hydrogen 
gas generator of any capacity. 

The explicit directions are given for the 
reason that the writer has known of amateurs 
who have been deterred from persevering in 
their experiments in lead burning, on account 
of the ditflculty they experienced in obtaining 
full command of the hydrogen gas generator. 

As before stated, the pressure of the gas 
generated in the chamber "C," immediately 
after the introduction of the sulphuric acid in 
the chamber ''B," through the opening ''P,'' 
has driven back the acidulated water through 
the supply pipe "F," away from the zinc and 
into the chamber '*B," causing the further gen- 
eration of gas to cease. 

The attention of the workman is called to 
the fact that the portion of atmospheric air 
in the chamber "C," before the water charged 
was introduced in the chamber "B", still re- 
mains in the chamber ''C," and is mixed with 
the generated gas. 



It is usual for the workman, before at- 
taching the rubber tubing to the hydrogen cock 
''K," to open the cock "K," and allow the mix- 
ed air and gas to escape into the atmosphere, 
closing the cock " K " the moment the water 
in the chamber " B " has run down to within 
about one inch of the bottom of the chamber 

The generation of pure hydrogen gas now^ 
takes place in the chamber " C," and the acid- 
ulated- w^ater is again driven back to the reser- 
voir " B," and there remains stationary, at the 
line '' S," until the further generation of gas is 
required. 

In this operation be caieful that no light 
is near, as the mixed air and gas escaping is 
verv exi)losive. 



As the hydrogen gas generator is now 
fully charged and ready for work, we wdll next 
consider the aerometer. 



^9 




AeronQeter. 



^^^^HE apparatus generally used for supply- 
YjlS^ ing atmospheric air to the hydrogen 
gas blow pipe, will usually be found 
to be crude and complicated arrangements, do- 
ing their work in an intermittent and irregular 
manner, requiring a helper or assistant's con- 
stant labor in keeping up the necessary supply 
of air 

We describe a simple, comj)act aerometer, 
that has been in use and thoroughly tested by 
many expert lead burners. 

It is so arranged as to give a constant 
and uniform supply of air at any pressure the 
lead burner desires. 

This is a matter of great imporlance to 
the workman, as, with a constant, uniform pres- 
sure of air, the gas flame can be regulated with 
an exactness not to be obtained where an 
irregular, intermittent supply of air is furnished. 



31 

Another con.^ideration in, that the time 
required in keeping the aerometer charged with 
air, is trifling, as it can be kept charged by the 
lead burner with.out tlie help of an assistant, 
or if keeping up the air supply be left to the 
care of a helper, the helper will have an abund- 
ance of time to shave and prepare the lead 
seams, ready for the lead burner. 

The aerometer consists of a cylindrical ves- 
sel, "X," of galvanized iron, of any desired size, 
open at the top and closed at the bottom, to 
which is attached two handles, so as to make 
the vessel convenient for moving or transporta- 
tion. 

Into this cylindrical vessel, "N," is inserted 
a similar cylindrical vessel, " M," open at the 
bottom and closed at the top, and about one 
inch less in diameter than the cylinder "X." 

On the top of vessel, '^M," is inserted an 
inlet air cock, " I," having a union coupling at- 
tached. 

On top of the vessel " M " and opposite to 
the inlet air cock " I " is inserted a similar air 
cock 'H," which is used as an outlet air cock. 



On top of the cylinder, "M," and near the 
center of the top is inserted a trap screw '' P." 

To charge the aerometer, fill the cylinder, 
"N," one-third full of water. Close the air cocks 
"H" and "I," tighten up the plug of the trap- 
screw "P,'* of the cylinder ''M." 

Now place the cylinder "M,'^ with its 
open end down, on the water inside the cylin- 
der ^'N." 

• Place a weight of from fifty to one hun- 
dred pounds on the top of cylinder " M." 

If the air outlet cock, '' H," be now 
opened, the air contained in the aerometer will 
issue from the cock "H," and at the same 
time the cylinder "M" will gradually sink until 
its lower open end comes in contact with the 
bottom of the cylinder "N." 

This action of the cylinder will give a 
constant supply of air through the cock " H,'* 
at a uniform pressure, as long as there be any 
air in the aerometer. 

In practice the supply of air is kept up 
by the means of the air-pump ''R," which is 



attached to the inlet cock " I " by means of a 
rubber tube. A x^^riodical pumping will keep 
the aerometer fully charged. 

The pressure of the air issuing from the 
cock ^^H" is regulated by the amount of weight 
placed on the top of the cylinder "M." 

When the workman ceases oi3erations and 
desires to remove the aerometer, the trap-screw 
*^ P '^ is slightly loosened, this permits the air to 
escape and the inside cylinder ^'M" to be easily 
withdrawn. 



fldjustment o¥ the plame. 



WE now have the hydrogen gas genera- 
tor and the aerometer fnlly charged 
with gas and air ready for operation. 

To utilize and mix the hydrogen gas and 
air, we proceed as follows : Slip one end of the 
section of y% heavy pure ruhher tubing on to 
the furrowed or roughed tail pipe coupling of 
the hydrogen cock " K/' Fig. 1. Slip the other 
end of the rubber tube on to the tail of the 
hydrogen gas regulating cock "T'^ of the brass 
mixing fork "Z.'^ connect the air outlet cock "H," 
of the aerometer, to the air regulating cock "S," 
of the mixing fork " Z," by means of a similar 
piece of rubber tubing. 

The outlet end of mixing fork "Z" must 
now be connected by rubber tubing to the brass 
flame jet holder ''X." 

The apparatus is now arranged to develop 
an intense non -oxidizing flame on any spot in 



So 

the lead seain the workiiian desires to direct 
it. The exi)ert can work all day long, drop 
by drop, on the ^^eam with this intense flame, 
which, guided by his skillful hand, melts in- 
stantly and cuts off like a knife from the edges 
of the lead to be joined, a single bead or drop 
of lead, and guides the drop to its proper place 
to make a solid homogeneous joint, connecting 
two pieces of sheet lead so perfectly that it is 
not possible to discover the point of juncture, 
and he retires from his day's labor with confi- 
dence and knowledge that every drop of lead 
melted has perfonned its -duty, and constitutes 
an homogeneous part of a sheet lead seam that 
he knows to be perfectly tight. 

But how is it with it the amateur? Let 
him take the flame from the hands of the ex- 
pert and try what he can do. 

His first attempt to approach the lead 
seam with the flame, will probably show a 
beautiful hole burnt through the lead or an 
ugly oxidized surface that cannot be managed 
by the flame unless the surface is removed by 
the shave hook. 



36 

It is impossible to convey to the amateur^ 
by means of cold type, the knowledge acquired 
by the expert, by long experience and practice. 

We can, however, assure our amateur that 
it is as easy to handle the blow pipe flame as 
it is to wipe a plumber's solder joint. 

Patience and Practice will, in a short 
time, give him that confidence and skill that 
will enable him to do good work. 

The first and most important point is to 
understand and obtain control of the blow pipe 
flame. 



SI 




^'1^'il '^' 

^y^/^ 



Fig. 4. 

Hydrogen Gas Flame. 



88 




Fig. 5. 

Working Flame. 



39 

The hydrogen cock " K," at the gas gen- 
erator, and the air supply cock "H," at the aero- 
meter, being opened full, gives the pressure of 
both gas and air to the mixing fork *'Z." 

If the regulating cock ''T" be now turned 
on full, and the issuing gas ignited, we will 
have a spreading, noisy, bi*ushy, indefinite flame 
of little heat and of great length. (See Fig. 4.) 

Tap the handle of regulating cock ^'T," 
gently, so as to cut off" the supply of hydrogen 
gas and reduce this flame to, say three inches 
in length. Then gently tap the handle of the 
air cock ''S" and admit air to the flame; with 
the proper quantity of air you will have a rapid 
darting flame, (Fig. 5), of about one and one- 
half inches in length, containing an inner 
pointed cone of blue flame. The apex of this 
inner cone of blue flame constitutes the non- 
oxidizing flame, and is the point of greatest 
heat. The outer flame encircling this blue cone, 
is vague, undetermined and of a pale reddish 
color, and is know^n as the oxidizing flame. 

It is well for the learner to study the 
properties and note the efiect of this compound 
flame. 



40 

Clean a portion of a piece of sheet lead 
b}'^ means of a shave hook, in the ordinary way. 

Bring the flame down quickly on to the 
cleaned lead, until a portion of the blue inner 
flame comes in contact with the lead, and note 
that the spot of lead melted w411 present a clear 
bright surface. This surface will remain bright 
if the flame is taken away w4th a quick move- 
ment, for the reason that you have melted the 
lead with the non-oxidizing flame, and removed 
the flame without allowing the outside or oxi- 
dizing flame to come in contact with the melted 
lead. 

Now bring the flame to the cleaned lead 
at another spot, keeping the apex of the blue 
cone about a quarter of an inch from the lead. 
The effect will be that the lead will melt, but 
much slower than in the former experiment, 
and when melted will be covered with a gray 
scum of oxide, in other words the lead has been 
melted by the oxidizing flame. 

Now again, on another clean portion of 
the lead, bring the flame down quickly and melt 
a spot of lead with the blue cone flame; this 
will give you a clean, bright spot of melted 



41 

lead ; now draw tlie flame slowly away from 
the bright melted spot and note that the instant 
the blue cone leaves the lead, the outer flame 
acts on and causes the formerly bright spot to 
become oxidized or covered with a rough, gray 
scum of oxidized lead. 

It is worse than useless to proceed to 
practice with the flame in joining two pieces of 
lead until the learner has the proportions of the 
gas and air adjusted so as to produce the proper 
flame. 

The quantity or length of the flame can 
be adjusted to suit the thickness of the lead or 
the position of the work. Should the learner 
find his flame too large, it is best for him to 
shut the air regulating cock "S," and then re- 
duce the quantity of hydrogen by gently tap- 
ping the handle of the hydrogen cock "T," 
thereby reducing the quantity of hydrogen gas 
and shortening the hydrogen flame. 

When the desired quantity of gas is ob- 
tained, gently tap the handle of the air regulat- 
ing cock " S," admitting air until the blue inner 
cone appears in a well defined pointed shape. 



Practice. 



i^ H E learner may now be considered 

7 familiar with the non-oxidizing flame, 

and be may attempt the joining of two 

pieces of sheet lead, in the manner known as 

butt seaming. (See Fig. 6.) 

The two edges of the sheet lead to be 
joined are prepared or cleaned by shaving, as 
shown at ''F," the pieces of lead are placed on 
the bench and the shaved edges brought to- 
gether. 

A seam of this kind is generally made 
thicker in the seam than the rest of the lead. 

The lead required to make this extra 
thickness in the seam is supplied from a tri- 
angular bar of lead, as shown in "E.^' 




Fig. 6. 

Flat Butt Seam. 



This seam is started at the point "G" by 
melting off a drop of lead from the bar ''E." 
This drop of lead, by the attraction of cohesion 
and directed by the force of the flame, becomes 
attached to and homogeneous with the melted 
edges of the cleaned portion of the sheet to be 
joined. 



The making of the seam thus proceeds 
drop by drop, each drop of lead being directed 
by and caused to unite with the preceding drop 
by a peculiar circular motion of the flame di- 
rected by the hand of the workman. 



The next seam that may be practiced on 
is knoW'U as the flat lap seam. 

This is w^here the edge of one of the 
sheets to be joined, laps or projects over on to 
the other sheet, as shown in Fig. 7. The 
method of making this seam is much the same 
as the flat butt seam, except that no bar lead is 
used, the material necessary to make the joint 
is melted from the front edge of the top sheet. 



4S 




46 



The drop of lead is melted from the front 
edge at "D," and directed by a quick motion 
towards "E," and then slightly downward until 
united with the lower sheet, when the union is 
made by the lead drop with the lower sheet, 
the flame is quickly removed in th-e direction 
of "D," to melt and carry towards "E," a fresh 
drop. 

By this peculiar motion of the flame in 
the hands of the workman, the edges of the 
lead are united drop by drop until the seam is 
completed. 

The edges of the sheet lead to be joined 
in the horizontal seam, lap in the same manner 
as in the flat lap seam. The position of the 
seam, however, makes it more diflicult for the 
learner. This seam has to be made upright, 
that is, on the side of a wall or tank, and 
should not be attempted until thoroughly pro- 
ficient in making the flat lap seam. 

The making of a workmanlike horizontal 
or upright seam, by means of the blow pipe 



47 

flame, is considered by iiuiiiy as evidence that 
the workman thoroughly understands the busi- 
ness of lead burning. 

Tliere is no reason why the learner who 
has become proficient in the making of a flat 
lap seam, cannot become equally proficient in 
the making of both the liorizontal and upright 
seams. 

By a little i)ractice he acquires the knowl- 
edge of the proper amount of lead to cut ofl", 
keep hot, and direct to the exact spot required 
to make a homogeneous junction of the two 
sheets of lead. 

The sheets of lead for tlie horizontal 
seam are prepared as shown in Fig. 8. "B" is 
the upper or back sheet, '^A" the lower or front 
sheet. 

The edges of both sheets must be cleaned 
or shaved. The shaving, however, need not be 
so wide as for the butt or the flat lap seam. 

The flame must be reduced in size, as the 
melted drop of lead required is much smaller 
than is used for the flat butt seam. 




Fig. 8. 

Horizontal Upright Lap Seam. 



49 

The learner can begin to practice the 
burning of an horizontal seam by fastening the 
pieces of sheet lead, on Avhich he desires to 
practice, to a piece of board by a few tacks 
driven through the sheet lead into the board 
to keep the sheets '^B" and "A," Fig. 8, in 
place. 

We presume he can burn a flat lap seam 
in a good and workman-like manner, if not, it is 
useless to attempt this seam. 

The learner that can make a fair flat lap 
seam, will be able to make a fair horizontal 
seam in four lessons. 

1st. Elevate the board on which the sheets 
for practice, "A'' and "B/' are fastened, at an 
angle of twenty-five degrees, see Fig. 9, and it 
will be found that a small amount of practice 
will give as good a seam as if made on the 
flat, 

2d. Increase the angle of the practice 
board to forty-five degrees and the learner will 
find that, with a little extra care, he can still 
make the seam. 




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til 

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51 

3(1. Iiu'rease the angle of the ]>ractice 
board to seventy degrees. The experience gained 
at the angle of forty-five degrees now assists 
him in the production of a satisfactory seam. 

4th. Place the practice board perpendicu- 
lar or at an angle of ninety degrees, and pro- 
ceed with the seam as if at seventy degrees. 

The results to the learner will be just as 
good a seam as he made at seventy degrees. As 
he has been brought by easy stages from the 
flat to the perpendicular and can, no doubt, now 
make a workmanlike horizontal seam, he is 
highly elated to find he can now do easily 
what he before found impossible, or at least 
extremely difficult. 

The learner now being in high spirits, 
from his success in making a workmanlike 
seam, from the flat to the perpendicular, may 
possibly ask his instructor to give him some- 
thing more diflicult. Should this be the case, 
we would suggest that he tip his practice board 
to twenty degrees over the x)erpendicular and 
try his horizontal seam at this angle. If suc- 
cessful, continue the declination of the angle of 



52 

the practice board, and if he can yhow a tight, 
workmanUke horizontal seam, directly over head, 
the instructor has nothing more to say. He is, 
indeed, a lead burner. 

The perpendicular or straight away up- 
right seam is usually made on the wall or side 
of a lead chamber or tank, and extends from 
the floor or bottom of the tank, upwards, or in 
a direction at right angles to the horizontal 
seam last explained. 

The flame used in making the upripht 
seam is of the same length, and the lead bead 
or drop, melted, of the same size as in the mak- 
ing of the horizontal seam. 

The learner, having mastered the horizon- 
tal seam, will flnd no trouble in making the 
upright seam. 

There is a slight difference in the direc- 
tion and run of the melted drop of lead, and 
the blow-pipe flame strikes the lead at a more 
acute angle than in the horizontal seam. This 
position can be seen in Fig. 10. 

The flame strikes the edge of the sheet 
lead ''A" at "F," cuts a drop of melted lead,. 



53 




Fig. 10. 

Upright Seam. 



follows and directs the drop by the force of the 
exuding pencil of gas flame to the point of 
union, and is instantly removed the moment the 
juncture is made by the drop of melted lead 
with the sheet "B." 

The seam thus grows in length, drop by 
droi:>, under the repeated action of the flame. 

The learner has by practice educated his 
hand and eye to control and place a heavy 
molten drop of lead at the exact point required 
to make a perfect homogeneous juncture of two 
sheets of lead with a portion of its own material. 



55 



Tl^eory o¥ Lead Burning. 



T|)T IS well to understand the philosophy of 
^ the operation of lead burning. 

The learner having a knowledge of the 
non-oxidizing flame, has no trouble in making 
a flat butt or a flat lap seam, as he finds 
that the law of gravitation assists him, as the 
drop of melted lead remains on the flat seam 
where melted, and submits itself to the laws of 
adhesion and cohesion, which at once sieze on 
the drop of melted lead and dispose of it in 
the exact sjjot to make a perfect seam. Not so 
on the horizontal and upright seams. Here we 
have a disagreement or a fight between physical 
agents and natural forces. Gravitation says to 
the melted drop of lead on the upright seam : 
you are wanted at once, come with me to the 
center of the earth. Cohesion and adhesion say 
to the melted drop: we will hold you with all 
our strength, do not leave us. The expert lead 



56 

burner takes advantage of the properties of the 
molecular forces of cohesion and adhesion, 
which forces, when combined with the force ex- 
pended by the flame issuing: from the blow pipe 
jet, are of sufficient strength to hold and man- 
ipulate a melted drop of lead of a certain size 
to the proper point of junction on the upright 
or horizontal sheet lead seam. 

This is the theory of the small bead or 
lead drop used in the horizontal and upright 
seam, as compared with the large flow^ of melted 
lead used on the flat seams. 

The attraction of gravitation is that phe- 
nomena in nature that causes all bodies free to 
move to fall towards the center of the earth. 
Cohesion is the force that unites two molecules 
of the same nature. 

In large masses of fluids the force of 
gravity overcomes that of cohesion. Hence, 
fluids acted on by gravity have no special 
shape ; they take the shape of the vessel in 
which they are contained. But in smaller 
masses cohesion gets the upper hand and the 
fluid presents the spheroidal form. 



This is geeii in drops of dew on the 
leaves of plants. It is also seen when fluids 
are placed on a solid which does not moisten ; 
as for example, mercury on wood. 

A number of sej^arate drops of mercury 
on a plain wood surface, if brought in contact, 
will cohere in one large globule. 

Adhesion is the molecular attraction ex- 
erted between bodies in contact. Adhesion takes 
place between solid bodies and fluids, and can 
be shown by dipping a glass rod in water; 
on withdrawing the rod a drop of water will 
be found suspended to the rod, as the weight 
of the drop tends to detach it, there must 
necessarily be some force sui^erior to this weight 
which maintains it there. This force is the 
force of adhesion. 

This force of adhesion is strongly devel- 
oped on the lead burner's seam between the 
cold lead and the melted bead or drop. 

From the foregoing the learner will real- 
ize that by practice he educates his hand and 



58 

eye to guide the forces of nature in producing 
useful results in the shape of workmanlike 
seams that show the skill of the expert lead 
burner. 



59 



After Thoughts. 



WE FEEL that our little essay fairly 
covers the points necessary to en- 
able the learner, by practice, to 
become an expert lead burner. He will, no 
doubt, meet with many difficulties, troublesome, 
simply because not fully understood. Many of 
these minor difficulties he Avill escape by com- 
mencing with a machine purchased from a re- 
liable manufacturer. 

It will never j^ay him to make his own 
machine. 



Never take a 
gas generator. 



light near the hydrogen 



When it is desirable to extinguish the 
flame at the blow-pipe jet, blow it out or jab 
it out with a quick motion. Then shut the gas 
cock "K" at the gas generator, and next the air 
cock "H" at the aerometer. 



60 

In charging the hydrogen gas generator, 
before pouring into the opening "P" the charge 
of sulphuric acid, see that the safety chamber 
^E" contains about two inches, in depth, of 
plain water. This forms a water seal for the 
fire-trap pipe "O," and extinguishes the flame 
should it recede through the jet "X," fork "Z,'' 
and hydrogen cock "K." 

Some experts make a y\ inch hole in the 
outer shell of the safety chamber, at a point 
(See W Fig. 2.) about two inches above the bot- 
tom of the chamber, and insert therein, a small 
wood plug, and by this means establish a water 
line in the safety box. The. withdrawal of the 
wooden plug allows surplus water to escape, 
thus keeping the upi^er part of the safety box 
free from water. 

It w411 be observed that if the safety box 
contained an excess of water, it would be liable 
to VjIow over into the rubber tubing and thus 
give the operator considerable trouble, by inter- 
fering with and extinguishing the gas flame at 
the jet. 



61 

It often happens that the jet flame be- 
comes suddenly broken or rugged. This may be 
caused by a small particle of dirt in the nozzle 
of the jet, in which case it will be necessary to 
unscrew the tip or nozzle and burnish the jet- 
hole by inserting a small plug of hard wood. 
The hole in the jet for four pound lead should 
be gV inches in diameter. Usually three jets of 
different sizes are sent with a machine by the 
manufacturer. ^ 

The rubber tubing used should be heavy 
quarter-inch tubing, so that it will not kink and 
close off the gas or air. The lengths usually 
used are two twelve foot lengths, one each to 
the air and gas, and one six foot length from 
jet to the fork "Z." Any desired length of 
rubber tubing may be used to connect the air 
pump " E," wath the aerometer cock " I." A 
length of six feet is furnished by the manufac- 
turers of the machine. 

It often happens that it is found con- 
venient to have a. length of hose sufficient to 
extend from the aerometer into the tank on 



62 

which the workman is employed. In this case 
the air supply can be kept up by the work- 
man without leaving the tank. 

It sometimes hap[)ens that if the gas 
generator Ibe working very hot that moisture 
condenses in the rubber tubing, passes through 
jet, and puts out the flame, making it neces- 
sary for the w^orkman to cease operations, de- 
tach the tubing, and blow out the water. 

At the close of the day^s w^ork, tlie rub- 
ber tubing should be detached from the con- 
nections of the machine and suspended from a 
hook in such a position as to allow the water 
to drain out during the night. 

A proper proportioned gas generator 
should, if properly charged, furnish a constant 
supply of hydrogen gas to the w^orkman for a 
period of ten hours, and should do its work 
quietly and without a blow and with a mod- 
erate degree of heat. 

When the job is completed, or at the 
end of the day's work, detach the rubber tub- 
ing, open the air cock "K,*' and let the acidu- 
lated charge run down. Open the drain plug 



63 

**D' and throw away the fluid contents of the 
generator. Pour a couple of bucket fulls of 
clean water through the opening "P/' and let 
the water run out through drain "D." This 
will clean out the generator and have it ready 
for the next day's work. Should you quit work 
and let the saturated acidulated solution stand 
in the machine, you will find next morning 
that the machine was clogged or choked by 
the crystalization of the sulphate of zinc. 



^M*^iJ?? 



